/*画面はみ出し対策*/
*,
*:before,
*:after {
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}

body {
  background: #efdec1;
  font-size: 14px;
  font-family: Verdana, Geneva, Tahoma, sans-serif;
}

header {
  margin: 0 auto;
  text-align: center;
  background-color: #76c1f4;
  color: #fff;
  width: 80%;
  border-radius: 4px;
  padding: 4px;
  position: relative;
}

h1 {
  font-size: 20px;
}

footer {
  margin: 0 auto;
  text-align: center;
  background-color: #8d9295;
  color: #fff;
  width: 80%;
  border-radius: 4px;
  padding: 8px;
  position: relative;
}

nav {
  margin: 16px auto;
  text-align: center;
  background-color: #fff;
  width: 80%;
  border-radius: 4px;
  padding: 16px 4px;
  position: relative;
}

nav>.nav-title {
  margin-top: 2px;
  text-align: center;
  font-size: 18px;
  font-weight: bold;
  color: #160d90;
  background-color: #7de8e4;
}

nav>.nav-desc {
  text-align: left;
}

nav>ul {
  list-style: none;
  padding: 0;
  margin-bottom: 16px;
}

nav>ul>li {
  margin-bottom: 16px;
}

nav>a,
nav>ul>li>a {
  font-size: 18px;
  text-decoration: none;
  color: rgb(108, 34, 34);
  border: 2px solid #ccc;
  border-radius: 4px;
  padding: 8px;
  background-color: #f5c577;
  cursor: pointer;
  box-shadow: 0 4px 0 #9e5d18;
  display: block;
}

.container {
  width: 80%;
  margin: 8px auto;
  background: #fff;
  border-radius: 4px;
  padding: 4px;
  position: relative;
}

#title {
  text-align: center;
  font-size: 18px;
  font-weight: bold;
  color: #160d90;
  background-color: #7de8e4;
}

#question {
  margin-bottom: 16px;
  font-size: 24px;
  font-weight: bold;
}

#choices {
  list-style: none;
  padding: 0;
  margin-bottom: 16px;
}

#choices>li {
  border: 2px solid #ccc;
  border-radius: 4px;
  padding: 10px;
  margin-bottom: 10px;
  cursor: pointer;
}

#choices>li:hover {
  background: #f8f8f8;
}

#choices>li.correct {
  background: #d4edda;
  border-color: #c3e6cb;
  color: #155724;
  font-weight: bold;
}

#choices>li.correct::after {
  content: ' ... 正解!';
}

#choices>li.wrong {
  background: #f8d8da;
  border-color: #f5c6cb;
  color: #721c24;
  font-weight: bold;
}

#choices>li.wrong::after {
  content: ' ... 不正解!';
}

#btn,
#result>a {
  background: #3498db;
  padding: 8px;
  border-radius: 4px;
  cursor: pointer;
  text-align: center;
  color: #fff;
  box-shadow: 0 4px 0 #2880b9;
  margin-bottom: 16px;
}

#btn.disabled {
  background: #ccc;
  box-shadow: 0 4px 0 #bbb;
  opacity: 0.7;
}

#result {
  position: absolute;
  width: 300px;
  background: #fff;
  padding: 30px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  top: 50px;
  left: 0;
  right: 0;
  margin: 0 auto;
  border-radius: 4px;
  text-align: center;
  transition: 0.4s;
}

#result.hidden {
  transform: translateY(-500px);
}

#result>p {
  font-size: 24px;
}

#result>a {
  display: block;
  text-decoration: none;
}